Distbict of colttmbia



0. P. MOORE.

TELEPHONE RECEIVER.

APPLICATION FILED JULY 30; :913.

1,1 94,765. Patented Aug. 15, 1916.

4 SHEETS-SHEET 1.

99 mm 7- 6 771m D. P. MOORE TELEPHONE REQWER; APmcme'w was JULY 30.1913.

Patented Aug. 15, 1916.

4 SHEETS-SHEET 2.

Q Q m w 97.8% W1 E M D. P. MOORE.

TELEPHONE RECEIVER.

APPLICATION FILED JULY 30, I9I3.

1 1 94,765. latol'afed Aug. 15, 1916.

4 SHEETS-SIIEET 3.

pawn

PELTON MOOItE,'OF WASHINGTON, DISTRICT OF COLUMBIA.

TELEPHONE-RECEIVER.

Specification of Letters Patent.

Patented Aug. 15, 1916.

- -mation filed July 30, 1913. Serial No. 781,990.

To all whom it may concem:

Be it known that 1, DAVID PEL'mN Moons, a citizen of the United States,residlng at Washington, in the District of Columbia, have inventedcertain new and useful Improvements in Telephone Receivers, of which thefollowing is a specification.

This invention relates to improvements in telephone receivers, and moreparticularly to that type by means of which the sound is greatlyamplified, without affecting the articulation, one object of the presentinvention being the provision of a receiver, 1n which the diaphragm isnot unduly stressed and in which the armature is connected thereto by alever. or system of levers, that multiply the vibratory movements of thediaphragm when the armature is affected.

A further object of the present invention is the provision of means foradjusting the coi1, whereby the air-gap is varied without varying thestress upon the diaphragm.

A still further object of the present invention is the provision ofmeans for adjusting the coil to vary the adjustment of the pole thereofrelatively to the fulcrum point of the armature, thus to increase ordecrease the distance of the magnetic eflect thereof upon the armature.I

In designs of receivers heretofore used in connection with loudtelephones, both for announcing purposes and in connection with soundreproducing machines, the diaphragm has been placed under varyingstresses, either by adjusting the lever connected to the diaphragm, orthe armature to and from the pole of the coil to vary'the air-gap. Inthese, the main objection lies, and this has been borne out byexperiments, in the connection with the diaphragm that has either toogreat or too little flexing action upon the diaphragm, such effecteitherplacing too great or too-little stress u on the diaphragm. It hasbeen discovered t at the best 'results are attained both as to loudnessand articulation, when there is-practicallv no stress upon thediaphragm, and also when the periphery of the diaphragm is clampedfirmly and not mounted with one or more cushions. In order therefore, tompunt the diaphragm as above set forth with practically no stressthereupon, and to properly vibrate the same to produce the highestefliciency in sound reproduction: the armature is fulcrumed' to one poleof a permanent magnet while the free end, which is connected to thelever or levers for operating the diaphragm, dis posed to be above thepole of the ccil or electro-magnet which is attached to be influenced bythe remaining pole of the permanent magnet. This electro-magnet,however, is the adjustable member and is so mounted as to be moved toand from the armature to vary the air-gap and to and from the 111- crumpoint of the armature to vary the point of attack of the pole relativelyto the armature.

To more clearly explain the manner of carrying out the above, attentionis invited to the accompanying drawings, in which Figure 1 is a sideelev.tion of the preferred form of receiver, partly in section, madeaccording to and embodying the present invention. Fig. 2 is a viewlooking from above that as shown in Fig. 2. Fig. 3 is a section taken online 3--3 of Fig. 1. Fig. 3 is a detail view of the electromagnet andthe means for varying the air-gap. Fig. l is a view partly in section ofa system of levers for'vibrating the diaphragm. Fig. 5 is a longitudinalsection thr'ough a modified form of receiver employing two diaphragmsand a central collecting chamber. Fig. 6 is an end view thereof. Fig. 7is a section taken on line 7-7 of Fig. 5. Figs. 8 and 9 are detail viewsof the mounting for the electromagnet shown in Fig. 5. Fig. 10 is a viewin elevation of the diaphragm chamber as shown in Fig. 1 with means forconveying and amplifying the sound vibrations at both sides of thediaphragm. Fig. 11 is a view illustrating the same principle asapplied'to the receiver shown in Fig. 5. Fig. 12 is a view similar toFig. 4, in which the flat spring is dispensed with... Fig. 13 is a sideelevation partly in section of still. another modified form of receiver.Fig. 14 is a section taken on line Pie-1416f Fig. 13. Fig. 15 is asection taken ,on line 1515 of Fig. 13. Fig. 16 is a detail view showingthe method of mounting the adjusting screw for the receiver shown inFig. 13.

Reierring to the drawings, and more particularly to Figs. 1, 2, 3, and3, the numeral 1 designates a bi-polar permanent magnetot usual form,the terminal or pole 2 thereof being shorter than the pole 3, which isslightly reduced. The frame, com used of the arms 4 and 4, is supportedrom the ma et 1, and carries the inner member 5, which with the outermember 6 forms the support for the diaphragm I. This diahragm ma he ofmica. or phosphor bronze, both of vihii h have been found excellent forthis work. rod or stem is-connected in the usual manner to thediaphragm. and is connected to the lever 9, which is pivoted at to thearm 4, a flat spring 11, being seated in the free end of the lever 9 andmounted in the log 12 carried by the arm l. This spring may be dispensedwith as shown in Figs. 4 and 1:. but it has been found that it tends tomaintain the lever 9 parallel with the diaphragm and to relieve thestress thrown upon the diaphragm. A. plate 13 onnects the lever J to thepin 14 carried by and in the free end of the armature 15, whose point offulcrum is upon the outer face of the reduced end of the pole 3, the lug'16 preventing the same slipping outwardly. The coil 11' has the outerend of its pole l8 disposed adjacent the armature 15. the end if), asshown in l igs. 1 and 3. being projected within the space between thepoles 3 and 2, and having an aperture 20. in which is mounted theeccentric or cam 21. keyed at 2). upon the stem 23. This stem is mountedfor rotation within the exteriorly threading adjusting sleeve 24.mounted in the threaded bores '5 and 21 of the arm 4 and the pole 2.respectively. Thus by rotating the stem :23, the pole l is moved to andfrom the armature l5 and thus the air-gap varied without :i ecting therelative position of the lever 9 and iiittpltl'flgl'lll. To move thecoil laterally and thus m-iae the end of the pole 1h near to or fartheraway from the pole i). and therebv vary the fulcrum of the armature. theinner end of the sleeve Ill bears against the end ll) of the pole and isopposed by the cone spiral spring '38. which rests against the oppositeside of the end it) of the pole and the nonmagnetic. plate :29 in whichthe inner end of the stem :23 is seated. The recessed head no of thesleeu- Z4 is milled so that the sleeve may be readiiv adjusted. Themilled head 27 of the stem 2-3 is disposed for ready access.

in the form illustrated in Figs. U, T, 8 and a. the sound collectingchamber 150 has the horn attaci ing member 31 at one side. the twodiaphragnis 7' and 7". being mounted at; opposite sides and plfll'kl'lfvclamped by the rings 5'. This receiver is a double one, and has twopermanent magnets 32. of the watchcase type atmpposite ends. ()ne of therespecti'v'e pole pieces ii and CH. is provided with the fuierumingblock 3. mrresponding to the pole 3 heretofore described. supportingarmature i5. whose pin 1 is connecttal by the plate 13' to the lever 9.This lever is supported at it), and is connected to the diaphragm by thestem 5. A flat spring 11 is mounted in the free end of the lever 9, andcorresponds to the spring 11. heretofore described. A block 35 ismounted for sliding movement by means of the screw 36, While the screw37 adjnstabl'y connects the inner end 19' of the pole piece 18', of thecoil 17' to the block. The inner end of the pole 18', as shown in Figs.5 and 8. is mounted in the pole piece 34 of the magnet 32 for slidingmovement. so that when the screw 37 is mar posed between the diaphragmT" and the.

armature l5" the free end of the lever 9, being connected by the plateor rod 39 to the lever 38 nearer the fulcrum point of the lever 38, astem 8* connecting the free end of the lever .55 to the diaphragmclamped in the members 5 and a. Thus the coil 17* a tl'ects the armaturewhich through the rod 13. actuates the levers i and 38, to multiplv thedistance of vibration in the diaphragm and consetpiently increase theloudness of tone given off thereby. The number of levers 3b ma v bevaried.

As shown in Fig. 10, the chamber 6' carries the amplifier tube (3 forthe main amplifier 4T. while to collect the vibrations at the rear ofthe diaphragm a chalnber (3 is provided and leads into the sleeve (3 andthe auxiliary amplifier 4S.

in Fig. 11, the form of receiver shown in Fig. I is employed, thechamber having its tube ill attached to the main amplifier i l. the twoauxiliary chambers 40 and 41 being connected to collect the soundvibrations from the outer sides of the two diaphragms (not shown) andthrough the tubes l2 and 43, come) them to the two auxiliary amplifiersl5 and -16. respectively.

By the arrangements as shown in Figs, 10 and 11, the greatest efficiencyin sound collcction is secured. these devices being particularlydesigned for use in connection with announcements at railroad stationsand the like. and for talking and singing motion pictures.

In the form of receiver shown in Figs. 13, 14, J5 and 10, there is noprovision made for varying the lateral position of the coil. 17*,relative to the fulcrum point of the armature 15, the member 49 of thepermanent magnet having the armature fulcrum end 50 and being connectedby the member 51, to slidably support the member 53 of the permanentmagnet, the spacing lug 52 of the member 51 and the a jacent portion ofthe magnet member 53 being provided with the sliding connection 54. Thefree end of the magnet, member 53, is slidably connected in a similarmanner at 56 and 57 to the spacing block and the arm 4. In order to movethe magnet member 53 consequently vary the air-gap, a bore 58 is formedin the end of the member 53, the "threaded nut 59 being slid in the slot60 from the sideto receive the adjusting screw 61. This screw isprovided with the annular shoulder 62 at a fixed point, and this isrotatable withinlthe bore 63 of the member 51, the thimble the operatingend 65, looking the parts as shown in Fig. 16, so that thescrew 61 maybe manipulated by the milled head 66 to longitudinally slide the magnetmem ber 53 and the coil 17*. a

What I claim, as new, is

1. A telephone receiver, including a permanent magnet,-an armature, adiaphragm operatively attached to the armature, a coil having its polein attractive relation to the armature and under the influence of thepermanent magnet, means adjustable at will for 'moving the coil to varythe air-gap between its pole and the armature, and means also adjustable'at will for moving the coil to vary the position of the pole relativeto the fulcrum of the armature.

-2.'A telephone receiver, including a permanent magnet, a diaphragm, asupport for the diaphragm, a pivoted lever having its free end operablyconnected to the diaphragm, the pivot of the lever being fixed,

an armature operably connected to the lever, a longitudinally andlaterally slidable coil connected to the permanent magnet and ha ing itspole in attractive relation to the ar mature, and manually adjustablemeans for sliding the coil to vary its relation to the armature.

3. A telephone receiver, including a permanent magnet, a diaphragm, asupport for the diaphragm, a lever having one end operably connected tothe diaphragm, a fixed pivot for the other end of the lever, an armatureoperably connected to the lever, a longitudinally and laterallyslidalile-coil under the influence of the permanent magnet, and manuallyoperable mear to: moving the coil to vary the air-gap beta-ecu the poleof the coil and the armature. A

4. A telephone receiver, including a permanent magnet, a diaphragm, asupport for the diaphragm, a lever having ong end opprably connected tothe diaphragm, a fixed pivot for the other end of the lever, an armatureoperably connected to the lever, a coil under the influence of thepermanent magnet, manually operable means for moving the coil to varythe air-gap between the pole of the coil and the armature, and a secondmanually operable means also for moving the coil to vary the position ofthe pole of the coil relatively to the fulcrum of the armature.

5. A telephone receiver, including a bipolar permanent magnet, one poleof which is longer than the other, a longitudinally and laterallyslidable coil connected to the other pole of the magnet, an armaturetulcrumed upon the longer pole of the permanent magnet, a diaphragmoperably connected to the armature, and manually operable means forsliding the coil to vary the airgap between the pole thereof and thearmature.

6. A telephone receiver, including a bipolar permanent magnet,one poleof which is longer than the other, a longitudinally and laterallysli'dable coil under the influence of the shorter pole, an armatureulcrumed upon the longer pole of the permanent magnet, a diaphragmoperably connected to the armature, and manually operable means formoving the coil to vary the air-gap between its pole and the armature.

7. A telephone receiver, includin a bipolar permanent magnet, one pole 0which is longer than the other, a coil under the influence of theshorter pole, an armature fulcrumed upon the longer pole of the permmnent magnet, a, diaphragm operably connected totheiarma'ture, means formoving the coil to vary the air-gap between the pole thereof and thearmature, and means for moving the coil to vary the position of the polethereof relatively to the fulcrum point i of the armature.

8. A telephone receiver, including a permanent magnet, a diaphragm, alongitudinally and laterally slidable coil having its pole under theinfluence of the permanent magnet, an armature under the influence ofthe pole of the coil, leverage multiplying meansconnecting the diaphragmand armature, and manually operable means for mov ing the coil to varyitsrelation to the armature, without changing the relative positions ofthe armature and the diaphragm.

9. A receiverhavinga bipolar permanent magnet, anarmature fulcrumed toone pole and extending above the other pole thereof, an electromagnet, Ta longitudinally and laterally movable carlrier for the electromagnctdisposed in magnetic relation to the perm? nent magnet, and manuallyzcperable means A for moving the carrier and its electromagnet to varythe relation of the pole of the electromagnet to the armature.

10. A receiver, including a bipolar per manent magnet, one pole of whichis longer than the other, an armature fulcrumed to the longer pole andextending toward the polar permanent magnet, a coil under the forholding it against transv'erse movement influence of one pole thereof,an armature and for moving the coil to place its polerelatively to thefulcrum point of the armafulerumed upon the other pole of the permanentmagnet, a diaphragm operably conture. nected to the armature, means formoving 16. A telephone receiver, including a diathe coil to vary the airgap between the phragm, an armature operably connected poles thereof andthe armature, and means thereto, a bi-polar permanent magnet, one formoving the coil to vary the position of pole of which extends beyond theother to the pole thereof relatively to the fulcrum form a fulcrum forthe armature, a coil havpoint of the armature. ing its pole, pieceelongated and projected 12. A telephone receiver, including a betweenthe poles of the permanent magnet permanent magnet, an armature actuatedand in magnetic attraction to the short pole, diaphragm, a coil slidablyconnected to the a spring interposed between the extension permanentmagnet for longitudinal and and one pole of the permanent magnet, anlateral movements relative to the armature, adjustable screw disposed toengage the opand means for moving the coil. posite side of the extensionto cooperate 13. A telephone receiver, including a with the spring toregulate the position of permanent magnet, an armature actuated the coilrelatively to the fulcrum point of diaphragm, a coil slidably-connectedto the the armature, and oscillatory means engagpermanentmagnet forlongitudinal and 'ing the extension to impart longitudinal lateralmovements relative to the armature, manually operable means forimparting longitudinal movement to the coil, and a second manuallyoperable means for immrtingvlateral movement to the coil.

movement to the coil tore ulate the air gap between the armature an thepoleof the ,coil. v

17. A telephone receiver, including a diaphragmyan armature operablyconnected 1-l.,1\ telephonen-eceiver, including a dia--/.thereto, abipolar permanent magnet, one

phragm, an armature operably connected thereto, a bi-polar permanentmagnet, one pole. of which extends beyond the other to form a fulcrumfor the armature, a coil dis- 7 posed for longitlulinal and transversesliding movements between the poles and having its pole under theinfluence of the short pole of lhe permanent magnet, and means formoving the coil to regulate the position of its pole to the armature.

15. A telephone receiver, including a diaphragm, an armature operahlyonnected thereto, a bi-polar permanent magnet, one pole of which extendsbeyond the other to form a fulcrum for the armature, a coil having itspole piccc elongated and projected between the poles of the permanent1uagnet. and in magnetic attraction to the short pole, means engagingthe pole extension to hold it between the poles of the permanent magnetand for imparting longitudinal movement to the coil, and cooperahlemeans engaging the extension upon opposite sides pole of: ,which islonger than the other and forms a fulcrum for the armature, acoil havingits pole piece extended and projected between the poles-of the permanentmagnet and in magnetic attraction to the short pole, a spring interposedbetween the extension and one pole of the permanent magnet, an

auljuslable screw disposed to engage the.

opposite. side of the extension to cooperate with the spring to-regulatethe position of the coil relatively to the fulcrum point of thearmature, said extension being provided with an opening therein, and astem actuated cam mounted in said opening, whereby the oscillation ofthe stem and cam imparts longitudinal movement to the coil.

in testimony whereof I afiix my signature in presence of two witnesses.

DAVID PELTON MOORE.

\Vitnesses a E. II. PARKINS, M. L. \VnrrmoK.

